Brake shoe



Nov. 13, 1934. PARKER r AL 1,980,225

BRAKE SHOE Original Filed May 21, 1930 INVENTOR5 HUMPHREY F PARKER 6kg E. House ATTORNEY Patented Nov'. 13, 1934 UNITED STATES PATENT, OFFICE BRAKE snos poration of Illinois Original application May 21, 1930, Serial No. 454,250. Divided and this application October 14, 1933, Serial No. 693,560

12 Claims.

This invention relates to brakes, and is illustrated as embodied in a novel shoe for an internal expanding automobile brake of the shiftableanchorage type.

6 An object of the invention is to provide in a simple and inexpensive but effective manner for the correct engagement with the shoe of such auxiliary devices as the brake anchor, the brakeapplying lever, the brake adjustment, and the 10 like. Preferably this is accomplished by directly forming the end or ends of the web of the shoe integrally in a novel manner for this purpose.

In the particular shoe illustrated in the drawing, one end of the shoe web is formed for engagement with the brake anchor, preferably having a generally circular notch to fit directly over a correspondingly-shaped anchor, to provide for pivotal movement of the shoe upon the anchor in applying the brake and for positioning the end of the shoe correctly radially of the brake when the brake is released. Just inside and outside the anchor the shoe has surfaces which are rounded or otherwise formed for engagement with thrust lugs on a brake-applying lever.

The lower end of the web of the illustrated shoe is formed with a relatively wide and shallow notch, preferably formed at the bottom of the notch with a convex rounded surface, for engagement with a brake adjustment or the like. Another feature of the invention relates to making the shoe partially flexible, or conformable to the drum, in the manner described below, to combine most of the advantages of both rigid shoes and flexible bands with a minimum of the disadvantages thereof. a

The above and other objects and features of the invention, including various novel and desirable details of construction, will be apparent from the following description of the illustrative embodiment shown in the accompanying drawing, in which: 7

The figure is a side elevation of one form of brake shoe embodying the invention.

The shoe selected for illustration forms part of 45 the brake assembly described and claimed in our parent application No. 454,250, filed May 21, 1930, of which the present application is a division.

This particular illustrative shoe comprises a cylindrical steel rim 10, to the outer face of which is riveted or otherwise fastened the usual brake lining 12, and along the center line of the inner face of which is welded or otherwise permanently secured a stamped steel reinforcing web 14. As more fully explained in our said parent application, the brake has certain springs acting on the shoe, and the web 14 is provided with openings 16 or other means for the attachment of these springs.

It will be noted that the web 14 is tapered, being of less height at the center of the shoe than 6 at the ends. A full'rigid shoe of a given length is safe for a given coefficient of friction, but unfortunately the coeflicient of friction varies and if it increases too much the shoe may grab. On the other hand, a fully flexible band is diflicult 6 to control, and is apt to become distorted in use. The conformable, or partially-flexible, shoe we utilize,-and which is formed as described above, obviates these disadvantages of rigid shoes and of flexible bands and yet has most of the advantages of both the rigid shoes and flexible bands. 1

The upper end of theweb 14 is shown formed with a circular notch 18 adapted to fit pivotally over a correspondingly-shaped fixed anchor or post 20. As explained in our said parent application, one or the other of the two shoes of the brake pivots on the anchor when the brake is applied. The described construction also pro-' vides for positioning the upper end of the shoe correctly radially of the brake when the brake is released.

Inside and outside (radially of the brake) the notch 18 and the anchor 20, the end of the web is formed with rounded surfaces 22 or the like, for thrust engagement with lugs 24 formed on the brake-applying lever 26. Lever 26 has a notch 28 in its end, to afford clearance for the anchor 20.

The lower end of the-web 14 is formed with a relatively wide and shallow notch 30, preferably having its bottom convexly rounded, for pivotal engagement with the adjusting device 32 described in our said parent application. This adjusting device comprises at its end a thrust memher 34 slotted at its end to embrace the end of the web 14 and pivot relatively thereto on the rounded convex bottom of the notch 30. The notch 30 prevents radial displacement of the thrust member 34 relatively-to the shoe.

While one ilustrative embodiment of the invention has been described in detail, it is not our intention to limit its scope to that particular embodiment, or otherwise than by the terms of the appended claims.

We claim: 1. A brake shoe having a rim and a web, with one end of the web formed with a circular notch for engagement with a brake anchor and with rounded thrust portions on opposite sides of said 110 notch for engagement with thrust lugs on an applying lever, and with the other end of the web formed with a relatively wide and shallow notch with a convex curved bottom for engagement with a brake adjustment.

2. A brake shoe having a rim and a web, with one end of the web centrally formed for engagement with a brake anchor and with thrust portions on opposite sides of said anchor for engagement with thrust lugs on an applying lever, and with the other end of the web formed with a relatively wide and shallow notch with a convex curved bottom for engagement with a brake adjustment.

3. A brake shoe having a rim and a web, with one end of the web centrally formed for engage ment with a brake anchor and with thrust portions on opposite sides of said anchor for engagement with thrust lugs on an applying lever, and with the other end of the web formed with a relatively wide and shallow notch having a base and end walls for engagement with a brake adjustment the base of the notch terminating at each end'with substantially angular corners.

4. A brake shoe having a rim and a central web, with one end of the web formed with a circular notch of less depth than the radius of the notch circle for engagement with a brake anchor and with rounded thrust portions on opposite sides of said notch for engagement with thrust lugs on an applying lever.

5. A brake shoe having a rim and a central web, with one end of the web centrally formed with a notch of less depth than one-half the width thereof for engagement with a brake anchor and with thrust portionson opposite sides of said anchor for engagement with thrust lugs on an applying lever. l

6. A brake shoe having a web formed at its end with a wide and shallow notch with a convex curved bottom for engagement with a brake adjustment.

'1. A brake shoe having a web formed at its end with a wide and shallow notch having a base and end walls for engagement with a brake adjustment the base of the notch terminating at each end with substantially angular comers.

8. A brake shoe comprising a rim and a web, a notch in each end of the web, the web being reduced in cross-section substantially at the center of the shoe one of said notches being wide and shallow and having a base and end walls angularly related to the base. 7

9. A brake shoe comprising a rim and a web, a lining secured to therim, the web having a notch in one end presenting a concaved surface and a notch in the other end presenting a convex surface, the web being gradually reduced from the respective ends thereof toward the middle.

10. A brake shoe having a rim and a web with one end of the web centrally formed for-engagement with a brake anchor and with thrust portions on opposite sides of said anchor for engagement with thrust lugs onan applying lever and with the other end of the web formed with a relatively wide and shallow notch for engagement with the brake adjustment, said notch having at least a maximum depth at each end there- 11. A brake shoe having a web formed at its end with a wide and shallow notch for engage ment with a brake adjustment, said notch having a maximum depth at each end thereof.

12. A brake shoe comprising a rim and a central web, a notch in each end of the web, the web being reduced in cross section substantially at the end of the shoe, and one of said notches being circular in form and of less depth than the radius of the notch circle.

HUMIPHREY F. PARKER.

BRYAN E. HOUSE. 

